Aluminium oxide is impermeable and, unlike the oxide layers on many other metals, it adheres strongly to the parent metal. If damaged mechanically, aluminiumâs oxide layer repairs itself immediately.
Saliva helps remove oral waste and cavity-causing bacteria, protects teeth from decay by neutralizing harmful acids, and helps re-mineralize tooth enamel. Saliva also keeps oral tissues healthy by preventing infection by controlling bacteria and fungi in the mouth.
1 parotid glands-produce a serous, watery secretion. 2  submaxillary (mandibular) glands-produce a mixed serous and mucous secretion. 3  sublingual glands-secrete a saliva that is predominantly mucous in character.alivary Glands and Saliva. In the histologic sections of canine salivary gland shown above, the cells stained pink are serous cells, while the white, foamy cells are mucus-secreting cells. Photo Credit: Credit: Richard Bowen. Saliva is produced in and secreted from salivary glands.